Essentially a single channel of the Mic-Pre IV, the Mic-Pre One features switchable phase, 20dB mic input pad, and +48V phantom power, plus a selectable 1/4" line/hi-z instrument input, all utilizing relays with gold bi-furcated contacts. Two large knurled aluminum knobs control the variable high-pass filter (0-200Hz) and continuously variable input gain, which is complemented by a full-width, 20-segment bi-color LED meter. The rear of the unit offers a Jensen transformer-isolated mic input and fully-balanced XLR output, plus a 1/4-inch line output. A fourth connector introduces DC power from the external power supply to the unit.